Theoretical design and study of Porous Carbon Nitride Fullerenes: Introducing a Novel Family of Cage Molecules

We introduce porous carbon nitride fullerenes (PCNFs), a novel family of cage molecules. They can be considered as the zero-dimensional (0D) counterparts of two-dimensional (2D) porous graphitic carbon nitrides, in a similar analogy to how icosahedral fullerenes are the 0D counterparts of graphene. In this theoretical study, we show how such structures can be designed from Goldberg polyhedra.

We perform a detailed investigation of the properties of two representative members of this family, icosahedral C₆₀N₆₀ and C₁₂₀N₆₀. Applying state-of-the-art DFT approximations and Reax-FF molecular dynamics, we perform a detailed investigation of their structural, vibrational, and electronic properties, as well as their thermal stability. Our results demonstrate that these molecules are dynamically stable. Additionally, their electronic state is robust, as evidenced by the large HOMO-LUMO gaps. The large values of their electron affinities suggest that they might be used in several applications as electron acceptors. Moreover, upon performing molecular dynamics simulations under NVT conditions with ReaxFF force fields, we showed that C₆₀N₆₀ and C₁₂₀N₆₀ are thermally stable well above 1000 K and 2000 K, respectively.

By inheriting the advantageous properties of their 2D counterparts, coupled with their distinct 0D characteristics, PCNFs represent promising structures for a range of applications. These include permeation, molecular trapping, and catalysis, offering potential uses that could extend beyond the capabilities of existing 2D graphitic carbon nitrides. The introduction of PCNFs establishes a significant new class of fullerene-based cage molecules, opening up exciting new directions in nanomaterials research and technology.